| 1. | The path of a magnetic flux in a transformer should have ? | |
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high resistance
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high reluctance
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low resistance
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low reluctance
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Report Question| 2. | A transformer core is laminated to ? | |
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reduce hysteresis loss
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reduce eddy current losses
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reduce copper losses
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reduce all above losses
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| 3. | The dielectric strength of transformer oil is expected to be ? | |
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1 kV
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33 kV
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100 kV
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330 KV
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| 4. | Noise level test in a transformer is a ? | |
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special test
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routine test
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type test
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none of the above
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| 5. | A good voltage regulation of a transformer means ? | |
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output voltage fluctuation from no load to full load is least
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output voltage fluctuation with power factor is least
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difference between primary and secondary voltage is least
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difference between primary and secondary voltage is maximum
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| 6. | The efficiency of two identical transformers under load conditions can be determined by ? | |
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short-circuit test
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back-to-back test
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open circuit test
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any of the above
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| 7. | Scott connections are used to convert ? | |
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three-phase supply to D.C. supply
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three-phase supply to three-phase supply
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three-phase supply to two-phase supply
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three-phase supply to single-phase supply
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| 8. | In a transformer maximum voltage regulation occurs when the power factor of the load is ? | |
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0.4
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leading
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lagging
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unify
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| 9. | As the supply frequency of a transformer increases its rating ? | |
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increases
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decreases
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remains unchanged
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none of the above
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| 10. | Which of the following statements is correct ? | |
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A transformer operates at power factor below a particular value
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A transformer operates always at unity power factor
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A transformer operates at a power factor depending on the power factor of the load
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A transformer has its own power factor
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